1. Field of the Invention
The present invention relates to an articulated-quadrilateral hinge assembly for vertical-movement doors, which is provided with a stabilizer bar that is quickly adaptable to different operating requirements.
2. State of the Prior Art
It is known that in articulated-quadrilateral hinge assemblies designed for opening furniture doors in a vertical direction with translation or combined translation-rotation movements, there are two articulated quadrilateral hinges that are disposed on the sides of the hollow space closed by the door and are connected to each other by a transverse bar. This bar is required because the two hinges have such a wide movement that otherwise synchronization of the two kinematic mechanisms would not be allowed. For instance, should the door be opened by pulling it from the right end, in the absence of the bar the right hinge would tend to be the first to open, thus causing an unacceptable side oscillation of the door.
To solve this problem, therefore, a transverse bar is used that is rigidly fastened to two homologous components of the two kinematic mechanisms so as to reduce the possibility of mutual angular displacements to the minimum.
While the exact fastening position of the bar is not of great importance to the ends of the kinematic movement (generally it is sufficient for it to be connected at any point along one of the two connecting-rod arms of the hinges), on the contrary the bar position acquires a great importance if the practical use of the hinge assembly is taken into account. In fact, if positioning of the bar on the upper connecting-rods at a location moved towards the door is considered, easy access to the bar is obtained and at the same time the bar fully moves away from the access opening to the piece of furniture and is not in the way when the door is open.
On the contrary, with such a positioning of the bar, upon closure of the door, the bar greatly moves downwards, i.e. towards the door centre line. While this is of no importance in the case of non transparent doors, if the door is made of transparent or semi-transparent material at least at the centre part thereof, the bar becomes visible through the closed door, which adversely affects the aesthetic appearance of same.
To obviate or reduce this drawback, the bar should be shifted upwards as much as possible; an ideal position from this point of view could be that in which the bar axis is coincident with the pivot axis of the upper connecting-rod to the piece of furniture. In the known art therefore solutions have been proposed in which the bar is located at a position very close to or coincident with the pin of the upper connecting-rod on the piece of furniture.
However, this solution too has a drawback, in that during opening of the door, the bar rotates upon itself but its axis does not move and therefore when the door is open the bar will be at the inside of the access opening to the piece of furniture, so that the access opening is limited and introduction or removal of objects is hindered.
Up to now it was the furniture-maker who chose which type of hinge assembly was in his opinion the most appropriate, i.e. the one offering a larger access opening or the one making the bar less visible through transparent or semitransparent doors (for instance, doors provided with a frame surrounding part of the pane of glass). This however has the disadvantage, among some others, that the furniture-maker is obliged to have two different types of hinge in stock so as to be able to choose the most appropriate, depending on the door to be mounted.
It is a general aim of the present invention to obviate the above mentioned drawbacks by providing an articulated quadrilateral hinge assembly with stabilizer bar that is directly and quickly adaptable to the different requirements.